The forest is a very quiet place. Thick trees form a ceiling that blocks the sun and any trace of breeze. The air is moist and clingy. So is the heat. Forest inhabitants slink stealthily through the brush. Thick vegetation strangles sound before it rises. Only the occasional call of a persistent bird manages to escape.

The forest also absorbs secrets, past civilizations entombed by the dense growth. The promise of discovery draws explorers into these long-deserted territories. That's what brought Ray T. Matheny, '60, professor of anthropology, into a forest in northern Campeche, Mexico--the search for Santa Rosa Xtampak, an ancient Maya city.

With students and a Maya guide, Matheny set out on three occasions to find the ancient city. His clues were notes from two explorers, John Lloyd Stevens and Frederick Catherwood, who found the site in 1840, and notes from archeologist George W. Brainard of UCLA, who rediscovered it in 1940. Now more than 20 years later, with Brainard dead, the city was again lost. So Matheny went looking.

On his third journey into the forest, as in previous trips, they hiked through the dense bush in near silence. But this day was different. Almost spookily, a startling cacophony rose out of the forest. The team followed the noise, and it grew louder and louder.

The records Matheny had of the lost site indicated there was a small rural complex near the site, a finca. It was occupied around the turn of the 20th century but had been left to ruin at the time of the Mexican Revolution.

When the team finally reached the sound, they were at the finca. The abandoned complex stood empty and still. However, tenants had moved into the finca's water cistern. Thousands of them. They were the source of the unusual sound. Frogs and snakes and other creatures had made their home in the abandoned cement cistern.

"I remember one green snake swimming in the water. It had a whole row of frogs sitting on its back," says Matheny. "They all made the loudest noise."

But the bellowing had led them to the site. As the notes promised, the lost city was close by. Machetes in hand, Matheny and his team began to explore.

The first thing they found was a giant rattlesnake. Coiled and ready to strike, the snake sat in the path of the Maya guide. He called out to Matheny. "That thing was the size of a wash basin," Matheny remembers. "I couldn't have that thing roaming around camp." So he instructed the guide to shoot it. With students on the expedition and the remoteness of the site, Matheny wasn't willing to risk snakebite. He later learned that this particular region was home to some of the world's largest rattlesnakes.

As Matheny explored the ruins, he carried a tape recorder to document his findings. He found a large mound he knew to be a palace. He could tell by a smooth slope up the side that there were stairs leading to the top. As he began to climb the side of the mound, he encountered another forest dweller.

"I brushed my arms up against a tree and a huge black and yellow spider landed on my right arm," recalls Matheny. "I said something into the tape recorder that I can't transcribe, and I flipped my arm as hard as I could. And it just ran chills down me."

Shaken but undaunted, Matheny continued to the top of the palace. When he reached the top he found a doorway to the inside. He took his machete, cut away the overgrowth crowding the entrance, and ventured in.

Without a flashlight, he stayed on the stairwell, winding down through the interior of the palace. At last he reached the bottom and found the door leading out. Again he cut away the overgrown branches, but also struck a beehive nested over the lintel of the door.

"Those darn things came right at me and I got six stings."

Matheny's encounters didn't stop him; rather, they introduced him to his neighbors for the digging season. Matheny and his graduate students mapped the site and studied the elaborate hydraulic system of chultuns--large man-made water cisterns found throughout the city.

Today Santa Rosa Xtampak is a tourist destination and is considered one of the largest and most important Maya cities of the region.